Bicriteria Block Splitting Heuristic For Lossy Compression

An apparatus for partitioning a block of an image to reduce quantization artifacts, comprising:

• a memory;
• and
• a processor, the processor configured to execute instructions stored in the memory to:
• estimate an expected entropy of the block;
• partition the block into sub-blocks;
• calculate respective amounts of visual masking for the sub-blocks;
• select, as a visual masking characteristic of the block, a highest visual masking value of the respective amounts of visual masking for the sub-blocks;
• combine the visual masking characteristic of the block and the expected entropy of the block to obtain a splitting indicator value;
• and
• determine whether to split the block based on the splitting indicator value.

A non-transitory computer-readable storage medium, comprising executable instructions that, when executed by a processor, facilitate performance of operations comprising:

• partitioning a block of an image to reduce quantization artifacts, comprising:
• estimating an expected entropy of the block;
• partitioning the block into sub-blocks;
• calculating respective amounts of visual masking for the sub-blocks;
• selecting, as a visual masking characteristic of the block, a highest visual masking value of the respective amounts of visual masking for the sub-blocks;
• combining the visual masking characteristic of the block and the expected entropy of the block to obtain a splitting indicator value;
• and
• determining whether to split the block based on the splitting indicator value.